Threader slot shuttle



Dec. 2, 1941. w. R. HEWTON 2,264,843

THREADER SLOT SHUTTLE Filed Oct. 10, 1940 FIG. 1

FIG. V

INVENTOR WILLIAM R. HEWTON.

AT ORNEY Patented Dec. 2, 1941 THREADER SLOT SHUTTLE William R. Hewton, Philadelphia, Pa., assignor to Collins & Aikman Corporation, Philadelphia, Pa., a corporation of Delaware Application Qctober 10, 1940, Serial N0. 360,567

7 Claims.

This invention relates to a threading block for self-threading shuttles such as are used in automatic Weft replenishing looms, and is particularly directed to the tensioning and thread control features thereof. According to these improvements a uniform frictional drag is imposed upon the thread on the second and all succeeding picks, the bobbin brushes offering suflicient resistance on the first pick for satisfactory operation without the addition of other drag.

The arrangement of parts is such that the tension is imposed at a point where the thread is devoid both of unevenness and of whirling movement and where its running position is substantially fixed, with the result that the tension applied is uniform and there is little tendency on the part of the thread to escape from under control of the tensioning member. Adjusting means are provided and the amount of tension is adjustable for various types and sizes of thread or conditions of weaving. Thread knots, slubs or other enlargements are passed without strain upon the thread or breakage thereof.

It is an object of this invention to provide tensioning means for self-threading shuttles which will offer a steady uniform tension to the moving thread after the first pick.

It is another object of this invention to even or iron out the thread before the application of the frictional drag or the tension thereto.

Another object is to provide a loom shuttle having tensioning apparatus which will open wide to pass thread knots, slubs and irregularities without undue strain or breakage of the thread.

Another object is to impose tension on the moving thread at a point near the delivery eye where its running position is substantially un changed by the unwinding action of the thread from the shuttle bobbin.

Another object is to provide tensioning means for self-threading shuttles which may be adjusted for various types and sizes of weft as well as for various condition of weaving.

Another object is to provide an arrangement of parts which may be readily mounted in the type of thread block ordinarily used in selfthreading shuttles.

These objects are accomplished, according to a preferred embodiment, by an arrangement of parts comprising a pivotable tension plate which is spring pressed against the thread as it passes over the curved surface of a fixed member, preferably an upright cylindrical post. The end of the shuttle containing the thread block W111 hereinafter be referred to as the forward end. The fixed post is located near the forward end of the longitudinal channel of the threading block and forms the surface against which the thread bears as it turns from longitudinal direction toward the side delivery eye. The tension plate has its pivot point across the longitudinal channel from the fixed post and is pivoted rearwardly to press against the moving thread on the forward side of the post just after it has made the turn. At this point the thread is devoid of any whirling motion set up by its unwinding from the bobbin. Moreover the thread in making the turn is evened out and somewhat flattened against the corner post. It will thus be seen that my tension is applied at a point where the thread is running smoothly and evenly with little tendency on its part to escape from under control of the tension plate. Furthermore, tension thus applied will tend to be uniform.

Portions of the pivotable tension plate and of the fixed member extend above the inclined line of the thread when taut between the delivery end of the bobbin and the side delivery eye of the shuttle. Engagement of the thread by the tension plate at the start of the second pick is thus assured, for as the thread is drawn taut by the flight of the shuttle, it is pulled down along the fixed member and under the tension plate. The upper end of the plate on the side nearest the first member is bevelled to assist entrance of the thread beneath it.

The pivotable tension plate and fixed member also extend down below the fioor of the longitudinal thread channel, so that escape of the thread downwardly from under the tension plate is prevented by the fioor of the channel.

In order that the tension imposed by the plate when the shuttle is moving forwardly may be equal to that imposed when the shuttle is moving rearwardly, the side delivery eye includes a pair of upright posts in longitudinal alignment between which the thread is caused to pass during weaving and the tensioning plate is so positioned or shaped that no part of it tends to cross the path of and deflect the straight lines of the thread between the fixed corner member and the side delivery eye posts. That is to say, the pull of the thread on the rearward flight of the shuttle is against the rearward face of the forwardly positioned side delivery post and not against the pivotable tension plate.

The forward post of the side delivery eye is 55 preferably in the form of a depending tapered pin, beneath which the thread is pulled at the start of the second pick, and which, by directing the thread downwardly under its point, aids in pulling the thread down and between the pivotable tension plate and the fixed member.

The arrangement of parts is clearly brought out in the following description and the illustrated embodiment, wherein- Figure I is a top plan view of the delivery end of a self-threading shuttle showing a portion of the bobbin and the threading block, including the improved tensioning means.

Figure 11 is an elevational view of one side of the thread block.

Figure III is an elevational view of the opposite side of the thread block.

Figure IV is a forward elevational view of the thread block.

Figure V is a bottom view of the tension plate adjusting screw.

As shown in Figure I, the shuttle I is provided with the usual bobbin chamber 2 and side delivery eye 3 from which the filling thread leads during weaving as it is withdrawn from the filling carrier or bobbin 4. Forward of the bobbin chamber the shuttle is provided with the threading block 5, having a longitudinally extending thread passage 6 and an open top portion 1 through which the thread T passes into the langitudinal thread passage on replenishment of filling. The threading block has a thread director 8. Between the forward edge portion of the thread director 8 and a cut-away portion of the shuttle body an opening is formed through which the thread may pass to the side delivery eye on the second pick following bobbin replenishment in a known manner. A lug or projection 9 engages the conventional opening in the shuttle body to assist in positioning the threading block.

The threading block, which is usually made of metal, has a floor [0, a rear thread guide H which guides the thread T to the longitudinal thread passage and which, together with extension I2 overlapping extension l3, retains the thread in the passage.

The general construction of the frames of threading blocks-is well known in the art and is intended to facilitate entry of the thread into and retention in the longitudinal channel during the first pick and to guide it to the side delivery eye near the start of the second pick.

The shuttle is equipped with brushes H which contact the thread as it unwinds from the bobbin l. These brushes offer suflicient frictional resistance on the first pick for satisfactory operation without addition of other drag.

The tensioning means of the illustrated embodiment of my invention is shown in detail in Figures II, III and IV, and includes a pivotable tension plate in the form of a gate 15 mounted on post l6 and pressed by spiral spring I! against the fixed corner post l8. Both post l6 and corner post l8 may be secured to the threading block in substantially upright position by being screwed up into the side wall extensions l2 and 13 respectively.

Spiral spring l1, one end of which is fastened to the gate, is coiled about post l and, in order that the amount of tension may be adjustable, its other end is secured to knurled collar I 9, mounted free on post l6 and having a stud 20 which fits into holes 2| drilled on equal or unequal spacings about the circumference of head 22 of the post l6. Except when adjustment is 7 being made, collar I8 is held pressed against head 22 by the action of the spiral spring and rotation is prevented by the stud 20 in one of the holes 2 I. To adjust the tension, the collar I9 is moved upwardly away from the head 22 until the peg 20 clears and the collar is then turned in the desired direction to increaseor lessen the-tension, after which the collar is permitted to be pressed again by the spring into fixed contact with head 22.

To insure engagement of the thread by the tension gate at the start of the second pick, the upper portions of both the gate and the corner post are above the inclined line taken by the thread when drawn taut between the delivery end of the bobbin and the side delivery eye of the shuttle, so that as the shuttle starts its return flight the thread is pulled obliquely downwardly about the corner post and under the tensioning gate, the upper edge of which is bevelled as at 23 to facilitate its entrance.

To prevent escape of the thread from under the tensioning gate, the corner post l8 extends down below the floor of the thread channel and is engaged by the downwardly extending portion 24 of the gate. Since the channel floor extends forwardly of the corner post, the thread cannot take up position about the post lower than the floor level, and consequently escape of the thread from beneath the tensioning gate is prevented.

The side delivery eye 3 includes a depending pin 25 positioned immediately forwardly of and in longitudinal alignment with eye post 26. The rearward face of the pin is perpendicular, but the forward face is tapered and serves as a continuation of guide 8 to direct the thread obliquely downwardly into the side delivery eye. The pin extends down substantially to the floor of the eye, which may be cut away on the forward side as at 21 to permit the thread to pass under the point of the pin 25. At the start of the second or return pick, the thread is pulled under the point of the pin by the flight of the shuttle and takes up a position between the eye post 26 and the pin 25, which position it maintains for the remainder of the weaving. In directing the thread downwardly under its point, the depending pin aids in pulling the thread under and into engagement with the tensioning gate l5.

On the rearward flight of the shuttle, the thread rides against the rearward side of the depending pin 25, and in order that the tension imposed by the gate on the rearward flight may be equal to and not greater than that imposed on the forward fiight, the position of the depending pin with respect to the position and shape of the tensioning gate is made such that no part of the gate tends to cross the path of or deflect the straight line of the thread between the cor ner post and the said pin. The pull of the thread on the rearward flight is thereby placed against the depending pin 25 and not against the tensioning gate.

Although not essential, I prefer to use a gate which is fiat between its pivot point and its point of contact with the corner post and to place the pivot point directly across the longitudinal thread channel from the corner post, so that the gate may press against the thread on the forward side of the corner post just after the thread has turned from longitudinal direction and is moving transversely toward the side delivery eye. Under this arrangement the tension is applied at a point where the thread is even and its running position substantially fixed, so that the thread will not be disposed to jump from under the control of the tensioning gate. Beyond its point of contact with the corner post the outer edge of the gate may be flared forwardly if desired, so that if slub or novelty yarn is being used in the filling the severed end thereof may at the time of bobbin replacement be drawn past the gate in the reverse direction without being caught and broken and possibly drawn thereafter into the weaving shed.-

Myimproved ten'sioning and thread control means may be conveniently and inexpensively mounted in the type of threading block ordinarily used in self-threading shuttles. The cast metal block may be readily machined and drilled for the addition of the tensioning parts, all of which are in the forward end of the block where they may be easily inserted and where they are readily accessible for adjustment and maintenance.

Having described a preferred embodiment of my invention but wishing to be limited only by the claims and the prior art, I claim:

1. In a loom shuttle of the self-threading type having a threading block provided with a longitudinal passage and a side delivery eye, an upright corner post about which the thread turns from forward longitudinal direction to the sid e delivery eye, a tensioning gate pivotally mounted on an upright gate post located across the thread passage from the corner post, a spring coiled about the gate post to press the gate rearwardly against the corner post, and means for adjusting the tension of the coiled spring.

2. In a thread tensioning means as set forth in claim 5, characterized in that the gate post is equipped with a head having a plurality oi' holes spaced about its circumference, and in that the means for adjusting the spring tension comprises a coll ar mounted free on the gate post to which one end of the spring is secured, and having a stud insertable in th holes of the gate post head.

3. In a thread tensioning means for a' loom shuttle of the self-threading type, equipped with a bobbin and thread and having a threading block provided with a longitudinal passage, the combination of a substantially upright corner post, a flat pivotal plate having its pivot point across the lo gitudinal passage from the corner post, a spring to press the plate against the forward side of the corner post and a side delivery eye including a depending-pin the rearward side of which is rearwardly of the extension of a line drawn between the pivot point of the gate and the forward side of the corner post.

4. In a thread tensioning means for a loom shuttle of the self-threading type, equipped with a bobbin and thread and having a threading block provided with a longitudinal passage, the combination of a substantially upright corner post, a gate post located across the longitudinal passage from the corner post, a gate pivotally mounted on the gate post, a spring coiled about the gate post to press the gate against the forward side of the corner post and a side delivery eye including a depending pin so positioned that its rearward face takes a full forward pull of the thread on the rearward flight of the shuttle.

5. In a thread tensioning means for loom shuttles of the self-threading type, equipped with bobbin and thread and having a threading block provided with a longitudinal passage and a side delivery eye, the combination of an upright corner post whose upper portion is above the line :taken by the thread when taut between the delivery end of the bobbin and the side delivery eye, a flat pivotal gate having a bevelled upper edge, a spring to press the gate rearwardly against the-corner post, and 9. depending pin in the side'delivery eye the rearward face of which is rearwardly of the extension of the line drawn between the pivot point of the gate and the forward side of the comer post.

6. In a thread tensioning means for loom shuttles of the self-threading type equipped with bobbin and thread and having a threading block provided with a longitudinal passage and a side delivery eye, the combination of a corner post, a pivotal tensioning member having its pivot point across the longitudinal passage from the comer post, means to press the tensioning member rearwardly against the corner post, and a depending pin in the side delivery eye against the rearward face of which the thread'bears on the rearward flight of the shuttle and so positioned with respect to the pivotal tensioning member and corner post that when the pivotal member is in contact with the corner post a straight line path is taken by the thread between the forward side of the comer post and the rearward face of the depending pin.

7. In a loom' shuttle of the self-threading type having a longitudinal thread passage and a side delivery eye, tensioning means comprising an upright guide member against which the thread presses as it turns laterally from forward longitudinal direction to the side delivery eye, a rigid pivotal tensioning member having its pivot point across the thread passage from the guide member and means to press the tensioning member rearwardly against the forward side of the guide member.

WILLIAM R. HEWION.

CERTIFICATE OF CORRECTION.

Patent No. 2,26h.,81 .5. December 2, 191;.1.

WILLIAM R BENTON.

It is hereby certified that error appears in the printed specification oftheahove numbered patent requiring correction-as follows: Page 5, first column, and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office v Signed and sealed this 27th day of January, A. D. 1914.2.

Henry Van Arsdale,

(Seal) Acting Commissioner of Patents.

line 56, claim 2,-for the claim reference numeral 5" read --l--; 

